Can hyperemesis gravidarum be prevented?

Since the cause of hyperemesis gravidarum is unknown and likely multifactorial, there is no certain way to prevent it from occurring. One small trial found that, in people who previously experienced hyperemesis gravidarum, preemptively treating the subsequent pregnancy with anti-nausea medications reduced the severity and occurrence of symptoms.^[1] It may also be helpful to be at a healthy weight and take prenatal vitamins prior to conceiving.